The co-founder of the opposition research firm that hired former British spy Christopher Steele to assemble a dossier portraying links between President Trump and Russia has refused an invitation to interview before the House Judiciary and House Oversight committees.

The lawyers for Glenn Simpson said the Republican-led committee’s “task force” and its investigation into Justice Department and FBI actions ahead of the 2016 presidential election “has demonstrated a propensity to flout rules of confidentiality in order to manipulate the record and prejudice witnesses.”